h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

The following nouns denote qualities that enable a person to achieve or accomplish something.
(1) Ability is the mental or physical power to do something: “To make a fortune some assistance from fate is essential. Ability alone is insufficient” (Ihara Saikaku).
(2) Capacity refers to the potential for acquiring that power: “The capability [women] have shown in the realm of higher education, their achievements in the business world, their capacity for organization... have been a revelation” (Susan B. Anthony).
(3) Faculty denotes an inherent ability: My lawyer has a faculty for detecting hypocrisy. Talent emphasizes inborn ability, especially in the arts: “There is no substitute for talent. Industry and all the virtues are of no avail” (Aldous Huxley).
(4) Skill stresses ability acquired or developed through experience: “The intellect, character and skill possessed by any man are the product of certain original tendencies and the training which they have received” (Edward L. Thorndike).
(5) Competence suggests the ability to do something satisfactorily but not necessarily outstandingly: The violinist played the concerto with unquestioned competence but limited imagination.
(6) Aptitude implies inherent capacity for learning, understanding, or performing: “She handled her brushes with a certain ease and freedom which came, not from long and close acquaintance with them, but from a natural aptitude” (Kate Chopin).

Twinkle Twinkle you're a star.
Now I wonder what you are!
Up above the rest so high,
what makes me think you're quite a guy.

The H2G2 Guild of Wizards